Although the Yoon administration quickly announced measures such as designating a special emergency area around Itaewon, the week of national mourning, and setting up special altars, Ha Kyooman, a representative for South Korea at the International Association of Emergency Managers, said government officials did not claim immediate responsibility for a late emergency response.

Ha said policymakers have not realized the importance of contingency planning for special events such as Halloween gatherings in Itaewon.

The cause of the stampede should be attributed to "irresponsibility by police in the region", Ha said.

"The regional police, as emergency responders, did not pay attention to monitoring mass gatherings around Itaewon during Halloween festivities," Ha added.

The investigation team should consist of all stakeholders, from police, firefighters and medical staff members, to vendors in Itaewon, survivors and victims' families, Ha said.

"Multiple perspectives will be fairly considered to determine the main cause of the stampede."

Yoon Hee-keun, head of the National Police Agency, made a public apology for the fatal crush during a news conference on Tuesday.

The police chief said officers received numerous reports about the crowd numbers, but the response was insufficient.

According to information released at the news conference, police began receiving calls related to Halloween crowds gathering in Itaewon after 6 pm on Saturday. Just an hour before the accident, multiple reports were received calling for police control in view of the huge crowds in the area, but no specific measures were taken.

Yoon Hee-keun said the police will carry out a thorough investigation to determine the cause of the incident and responsibility.